a) Field of the Invention
The present invention relates to a disk array structure, and more particularly to a disk array structure which, by an assembly design of a housing, a connection seat, and at least two disks, is easy to carry, convenient to extract the disks, cooled down quickly, manufactured quickly, provided with lower manufacturing cost, able to serve as a mouse pad, and convenient to swap for use, thereby being applied to all kinds of disk arrays or the like.
b) Description of the Prior Art
Since availability of a PC (Personal Computer), a hard disk has been a storage device that is used most often. However, in terms of speed, the hard disk is one of the weakest equipment in the PC, comparing with a CPU (Central Processing Unit) and a RAM (Random Access Memory). In order to accelerate entire data streaming of the computer, and to increase a throughput capacity of storage, thereby improving security of data in a hard disk, a design of a disk array arises. The disk array is called a RAID (Redundant Array of Inexpensive Disks) in short, and its working principle is to use make a disk set in an array fashion, for improving the data security, in association with a design of distributed arrangement of the data. The disk array is an improvement method primarily developed to solve the problem that the hard disk is not able to match the CPU and the memory in terms of the capacity and the speed. The disk array includes a large-scale disk set assembled by a lot of inexpensive disks having smaller capacity, higher stability, and slower speed, using an additive effect from provision of data by the individual disk, to improve an efficiency of the entire disk system. In a mean time, while saving the data, the data are divided into a lot of blocks which are stored respectively on each disk, by using this technology. In addition, a concept of parity check can be also used by the disk array, such that when any one hard disk in the array malfunctions, data can be still accessed, and the data in the faulty hard disk can be computed and then be re-placed into a new hard disk, upon re-constructing the data.
The disk array exists in a system to emulate a logical disk by using more than two hard disks. A disk array controller is used to realize the existence of the disk array and to emulate all kinds of levels by using different types of arrays. The levels of the RAID which are addressed and applied most frequently are 0, 1, 0+1, 3, and 5. Other levels that are rarely used include RAID 4 and RAID 6. RAID 0 proposes a concept of using the disk array to store data in parallel, using a plurality of hard disks to parallel store different parts of a data. A general approach is to divide the data to be stored by a block of a specified length, with a first block being stored in a first hard disk of the array, a second block being stored in a second hard disk, and so forth. The length unit of the block can be a sector, a cluster, a track, or even an entire cylinder. On the other hand, RAID 1 proposes a concept of disk mirror to secure the data. An original proposal uses two disk drives with a same capacity to store a same data. By adding another hard disk to store the same data, a risk of data loss by failure of one of the disks can be reduced. In Windows NT (New Technology), a user is permitted to use a disk partition of the same capacity to build up the disk mirror, without being limited to using a size of the entire hard disk, so as to improve flexibility in using disks of different capacities. For example, the user can purchase a hard disk with a larger capacity, and use some partition of the hard disk to serve as a mirror of some hard disk, with the other partition being used for other purpose. Similar to RAID 0, RAID 2 also uses the disk array to store data in parallel. However, other than RAID 0, RAID 2 distributes data to each disk drive by bytes, not the large block of RAID 0. In other words, in RAID 2, a first byte of the data is stored in a first disk of the array, a second byte is stored in a second disk of the array, and so forth, thereby similarly improving the efficiency of data accessing. Comparing to RAID 0, as RAID 2 uses the byte as a unit of distribution, each read or write operation will induce all disk drives in the array to read or write simultaneously. RAID 2 also uses a plurality of extra disk drives to store an error correction code (ECC) or a parity check code, to increase a fault tolerance of the data. Adding every one such disk drive represents that a number of faulty disk drives that are tolerable for the disk array will also be increased by one. The purpose of the error correction code is that when some disk drive malfunctions, correct data can be still recovered from the data of other non-faulty disk drives, through computation. The degree of data recovering will depend upon a proportion of the number of error correction disk drives in the total number of disk drives.
It is known that the conventional disk array structure includes primarily a housing, a circuit control board and a plurality of disks. An interior of the housing is provided with a plurality of disks which are stacked longitudinally, and each disk is connected to a connector on the circuit control board, thereby forming the disk array. However, for the disk array structure, as the interior of the housing is disposed with the plurality of longitudinally stacked disks, an entire volume will be larger that it is inconvenient to carry. Furthermore, if each disk is to be swapped, as there is no related handling member, it will be inconvenient to swap the disk. Therefore, the conventional disk array structure cannot still fit with the user's need in practical application.